The high frequency of gallbladder cancer in women suggests a role for estrogens in its development. The aim of this study was to study the immunohistochemical expression of p29 estrogen receptor associated protein and pS2 estrogen induced protein in 111 pathological samples of gallbladder carcinoma, coming from 88 women and 23 men, 30 metastases of gallbladder cancer, coming from 25 women and 5 men and in 25 non-tumoral gallbladders. In the latter, p29 protein was positive in 12 samples (48%) and pS2 in 15 cases (60%). p29 was positive in 40% and pS2 in 32% of tumors. p29 expressed with higher frequency in metastases than in primary tumors (57 and 31% respectively, p<0.02). Early tumors had a significantly lower expression of p29 than advanced tumors or than metastases. Both proteins expressed in 18% of samples (synchronic expression) whereas one of both proteins did so in 60% of cases (asynchronic expression). We conclude that most gallbladder cancer samples express proteins associated to estrogen receptor or induced by estrogens.